Manufacture of flexible tubes



' Feb. 14, 1928.

J. POBEREJSKY MANUFACTURE OF FLEXIBLE TUBES Filed Oct. 22, 1923 Patented 14., lhfid.

untrue onceuns Postnatal-rs,

sore-consensus, ritancnf MANUFACTURE til? TEEES.

Application filed October ca, 1923, Set-tat Ito. er {52, and in France idovember it, 1922.

Hitherto textile tubes have been generally made either of flexible material such as rubber, leather, or similar material always containing a rubber composition, or made of e helical metal bands or strips in which a tight joint between the bands or strips was ensured by means of rubber, or asbestos, or by the pressure of the bands against each other. Such tubes could be used with satisfactory to results for liquids which do not corrode the composition of the tubes, and in cases whens the piping is not exposed to vibrations. But

' for motor cars and aerial machines, that is to say machines exposed to constant vibral tion, such flexible tubes are not strong enough, and leak, either on account of the vibrations displacing the joints between the metal bands of tubes, or owing to the materials containing rubber gradually disinte- 2ft grating under the action of hydrocarbons.

Moreover, no existing flexible material, the elastic properties of which can be compared with those of rubber, is free from liability to corrosion by hydrocarbons.

This invention relates to the manufacture of a flexible tube that can easily withstand vibrations, owing to itsbeing made without joints, and of a single material'which is unaffected by hydrocarbons.

Accordmg to this invention the tube is formed of a sheet of cellulose or similar material or a combination of materials of the cellulose group provided that 'the material used canbe'rolled into thin sheets similar '35 to sheets of paper.

ider to render it flexible, it is passed between two wire springs; one of the springs being mounted in the interior of the tube, and the other spring being wound round the outside of the tube, and the convolutions of the second spring lying between the convolutions of the first spring. -Thus the wall of the tube is forced to assume the shape .of a sinumaterial hereinafter described, and the procsoidal curve between the said two springs. The chief point in this operation consists in arranging a large excess of material between the springs. To that end, a cellulose tube is taken ot'a diameter slightly greater on than the final diameter of the tube to be obtained. By forcing the said larger tube into the convolutions of the inner spring which is of a smaller diameter, the material will be plaited,'and in addition there will also be formed in infinite number of minute bellows-like folds which are disposed ciress of manufacture will be clearly understood by referring to the accompanying drawing which shows the flexible tube in section, in the course of its manufacture.

Arod or mandrel A is used, of 'a diameter equal to the inside diameter of the tube to be manufactured. Around the said mandrel is first wound the wire B to constitute the inner spring or armature of the tube. This winding is done in a helical line, intervals equal to the diameter of the wire intended'to constitute the second spring being left between the successive convolutions.

The spring B being thus wound about the mandrel A, over the same mandrel is placed a cellulose tube C previously-prepared in the manner hereinbefore described and having a diameter greater than the diameter of the first winding B. The tube is then forced intothe spaces left free between the various convolutions of the spring B, by winding over the-tube and in the said spaces a wire D, as shown in the drawing, so as to form the outer spring.

:The tube being withdrawn.

Owing'to the said two springs constitut ing permanent parts of the tube, the'latter possesses a'great strength. The inner spring B prevents in fact the finished, the mandrel A lis to prevent any tube from collapsin under the action of atmospheric pressure in the event of a vacuum being produced in its interior.

As regards the outer spring D, it firmly 5 holds the material when a liquid or gas is protected by braiding it over with metallic or other thread, by enclosing it into any protective sheath.

The tube according to this suitable for any purpose, and its use is of special importance for piping'for hydrocarbons in machines exposed to vibrations such as motor'cars, aeroplanes or the like.

Having now particularly described and as c'ertained the nature of my said invention,

and in what manner the same is to be performed, I declare that what I claim is 2-- A flexible sheet-cellulose tube, permanently provided with interfitting outer and inner,

spiral windings of wire forming a multitude of transverse plaits in the tube around the convolutions of both windings, said, plaits having an infinite number of minute circumferentml, bellows-like folds formed in the de- 1 I pres'sions of the plaits.

invention is g In testimon whereof I afiix my si nature.

, JlloQUEs PoBEREJsKY. 

